Thursday , January 21 2021

Roaders are trying to produce more robust surfaces from recycled plastics



Total plastic made from the twentieth century. In the 1960s, not 10% were processed. Most of the time, plastics simply emit and fall into landfills. Some of the plastic garbage is thrown into the wild, from where you can get to the rivers and from them – at sea. As we improve, the problem of plastic waste will be even more serious. For example, this year there should be about 380 million. tons of plastic, therefore three times larger than bitumen, used mainly for the development of the world's roads – produces 120 million per year. tonnes.

These materials have similarities. Plastic is made from petroleum products and bitumen is a byproduct of petroleum refining. Both are polymeric – they consist of long molecules that have a strong connection. This ensures the strength of the plastic, contributes to its durability. These features are also good for road users. When laying a road, hot bitumen reinforces the aggregate of stones and crushed stones and generates a coating, commonly referred to as asphalt. All this has led people to think: why not substitute one polymer for another?

Products made from recycled plastics, such as gutters and sewage pipes. Now you are interested in using it on the road. On September 11, a 30-meter bicycle trail opened in Zwolle, Holland, with a 70% cycle path. recycled plastic, and what's left is polypropylene. In this section, a new product, PlasticRoad, is being developed, which together with the French oil and gas company Total is developed by two Dutch companies – the KWS highways construction company and the plastic tube producer Wavin.

PlasticRoad is a prefabricated product. Segments delivered at the factory are placed on properly prepared substrates such as sand. The segments are made hollow, they can be introduced into drainage systems, pipelines or power lines. Sections 2.4 meters long and 3 meters wide were made for the Zvol project. They are equipped with sensors to measure temperature, bending and outflow of water in drainage systems. Nearby, Githorne, another experimental cycle lane is underway.

Not only durable but also intelligent

If the idea fails, inventors expect it to be developed and produce segments made from recycled plastics only. There will be a row of hiking trails, parking lots, railway platforms. Finally, it is planned to produce segments and roads. They can be equipped with sensors for traffic monitoring. In the long run, the contours in plastic roads could be used to support the electrically driven, stand-alone transport.

According to companies, prefabricated plastic roads should serve 2-3 times more than usual. The price would also decline, mainly due to the fact that the roads could be built almost three times faster. A slippery coating, including debris, traditionally used for road construction, can be included. In addition, modified old segments can be recycled. But engineers will monitor how the track will withstand wear, as well as whether the bore creates a resonance that would cause that road to cause a lot of noise.

Recycled plastics can also be used in other ways – to blend it with hot asphalt bitumen. This pavement will soon be placed on the campus of the University of California, San Diego, to test various roadside plastic liners developed by the British company MacRebur. According to Toby McCartney, 2015 The company, which founded this company with a group of colleagues, all mixtures are made of difficult to recover plastic, which often reaches the landfill.

MacRebur plaster is clean, scraped and finely chipped in chips or granules. When placing or repairing roads, it is planned to carry out these works on site, so that local roads can be built from local waste. Each blend may contain about 20 different polymers, adapted to specific surfaces. A mixture can fit one bus lane, ie For heavier transport, the other would provide greater flexibility in the arc and, due to the lateral forces of the wheels, the tensioned surface may be missing, for example, in a transport ring . The coating can also be applied in very hot or cold conditions. And since the plastic is filled with small holes through which water enters the surface, the pavement is damaged, changing the asphalt can reduce the pit.

The company's plastic blends are already used for road coatings, parking lots and airport runways in several countries. The oldest project is probably the road in Cumbria, in north-west England, where trucks usually travel. He needed new coverage for about six months, but according to T. McCartney his condition was excellent after mixing in plastic two years later. After upgrading the cover, the old one can be recycled again.

Cleaning and sorting plastics made from different polymers can be very expensive, especially for low value products such as packaging. But T. McCartney says that bitumen shifting is profitable because, for example, in the UK the ton of bitumen can cost around 400 pounds. And for the standard road pavement, the additive made from recycled plastic adds 300-350 pounds per ton. Adding an additive would not require an adequate amount of bitumen, which could save you money. Now add-ons are replaced by 5-10% bitumen, but some can be increased up to 25%.

T. McCartney came up with specialized accessories for recycled plastic, seeing how holes are sometimes handled in India. The collected garbage is dumped into a hole, dipped in diesel and burned to form a solid mass. It is a crude option that pollutes the environment, but somehow helps to solve the problem. Occasionally in India, shredded plastic is mixed with bitumen and road construction.

Australian travelers also begin to use recycled plastics. In the suburbs of Melbourne, in Creighborne, this year, a 300 mile section of Rayfield Prospect is completed from the material called "Plated". It produced more than 200 thousand processed. plastic bags and packaging, crushed 63 thousand. glass bottles and used 4,5 mil ink. cartridges. After mixing all the components, 50 tons of recycled asphalt were produced and 250 tons of road pavement were produced. The characteristics of this road will be evaluated.

Stuart Billing of Downer, who took the floor, said that the cost of building roads from recycled materials is the same as traditional ones. However, it is expected that the road is more used and more resistant to heavy traffic.

Craigiebernay officials estimate that the amount of waste that was not deposited in the landfill would have been spent on the way Rayfield Prospect was built in garbage containers over the last ten years. Local councils are more likely to receive complaints about road conditions, especially in wells. And in Australia and elsewhere, homes would probably have been separated and recycled to get more plastic if they knew they could travel on even smoother roads.


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